Internal-combustion engine



June 12. 192s. t 1,673,183

E. R. BURTNE'T INTERNAL GOMBUSTION ENGINE Filed D60. 20. 1926 3 Sheets-Sheet l June 12, 192.8.

E. R. BURTNETT INTERNAL COMBUSTION ENGINE Filed Dec. 20. 1926 5 Sheets-Sheet WERE@ INVENTOR June l2. 1928. l 1,673,183

E. R. BURTNETT INTERNAL COMBUSTION ENGINE Filed Dec. 20. 1926 5 Sheets-Sheet 5 .Il I

` 17 l1 E 29. 3l\\ V Il 1 ifi-5. 'will 3M I .In l 10- l5 3j 'QL v 0/ Y 3 of l ,e N (NVENTOR Patented June 12, 1928.

xnve'nnrr nn'un'rnn'rr, or Los ANGELES, cnr-r enivre, -Assrenoa'ia'v DIRECT Sinvii fMEsNn v.Assiannientare, v'ro THE feuroivroirrvn Vanves consonA'r1oN,'oF*nENo,

vNEVADA, A CORPORATION OF NEVADA.

INTERNAL-COMBUSTION ENGINE.

Application ined December zo, ieee. -serial ivo. nasse.

My invention relates to Atw'o stroke cycle internal, combustion engines, 4and the principal objects of my invention are, tfofprovide in a two stroke cycle internal combustion engine apair of axiliaiy pistons'to the Working piston of al combustion chamber. lTo adaptone only of the auxiliary pistons toa valve function, v'the character vof the valve function being charge admission and 'to employ the second auxiliary piston to Counter balance 4the admission valve piston inrec'ipro'catory inertia and internal combustion pressure counterd'rive influence.

,In'anyl case ofa two stroke cycle engine wherein' fa supercharg'e induction of fresh fuel charge over the range o'f straight scavengingfand initial combustion chamber volux'ne of atmospheric value is desired, some means of providing `a fresh charge'admission 'passage communication -between the source'o'f 'fresh charge pui'npin'g 'andthe combustion chamber after the exhaust ports of the combustion chamber have been closed must be devised, A, piston vof conventional form'provides 'the desirable structiire for adaption to thefuntion of 'valving the admission co'n'i'inunication registration and cutofi' in so far as 'the 'valving vis concerned. However in order to cause the admission communication to remain in registration after the exhaust `:ports 'have been closed. in an engine wherein the exhaust ports are formed in the VWall of 'the Working cylinder andthe Working pist-on provides the necessary ar'i'dvusual exhaust por't cutoff, the 'crank pin to which the piston valving` the admission 'ports is connected must be relatively disposed late' rotatively With respect to the position of the main crank pin to which the Workingr piston which is adapted to the exhaust port cutoff is connected. l n

This arrangement of crank pin relationship det-elops an undesirable opposed driv-` ing influence to-'the cranks frominternal pressures, since the Working piston necessarily n'i'u's't be of greater stroke sweep displacement than the stroke sweep displacement of the admission valve piston, the compression clearance chai'iil'ierw'common to the Working piston and admission valve piston Will beof *the least displacement at tlie'moment the Working piston 'reaches' head end dead center.v with a corresponding vWorking pistonrcrank pin position of head end dead center and to, accomplish a desirable admission c'ommunic'ation.y registration lag of cutoli','ofv.er the exhaust port cutoff, the crank toavhich the admission i. valve v,pis't'o'n is attached Would be in a ,relative rotative position snbstantially 400 before head end dead center, the admission valve piston being ythe corresp'ondlingv stroke travel distance before head'end dead center.

'Obviusly the combustion lmust occiir vat thefinement ofthe maximum compression 'pressure in the 'clearance chamber ivhicli maximum is attained when the clearance chamber displacement yis of a minimum resulting 4from the Workinfgfpis'ton 'being in a most headivardly position vof its'stroke.

`This being the case, a driving influence ivill vbe 'transmitted to the rotary parts of the engine in direct proportion 'to the square of the, admission valve piston 'and the ratio o'fvitls stroke relative 'to the square ofthe Werking' piston, its 'strok'e and [the 'number of dcgree'sthe crank to the ladmission valve piston 'is arranged late rotatively with respect to the rotative position ofthe crank to which 'the Workin-gpiston isA connected. lherefor, i't is the object of my present invention to 'provide a pair of auxiliary pistons to a given coi'nbu'stion chamber designed to function in two strokecycle time, to adapt one Iof the said'auxiliary pistonsto the admission valve purpose,- to provide the two auxiliary pistons of exact form, Weight and dimension, facilitating `ease of manufacture, intercl'iangeability.' y

The inertia force dei'felo'ped Aby the reciprocatory movement of either of t-he two auxiliary ,pistons being 'equally countered by the reciprocatory inertia lforce of lthe other, vthe arrangement of the pair `o'f auxiliary pistons adjacent and axially parallel permits the reduction of thc couple betv'een the plane of the respective reciproc'atory forces.

AI propose to arrange the ytwo crank pins to ivhich a given pair of auxiliary pistons of one combustion chamber are connected sfi'bsta'ntially 180 apart, hence, v.the pair of auxiliary pistons being of exactly the same d 'imension in every respect the pressure influence 'transmitted to the crank shaft lvvi'll be equal and opposed. When combistion 'occnrs `and internal driving pressure is developed vonthe head 'area of the' respect-ive pistons, the only effective driving medium will be the area of the working piston since,

. the other ofthe twoauxiliary pistons to a given combustion chamber will be 400 before crank end dead center. l

The advantages of the conventional'form of piston for admission valve use in a'twof4 stroke cycle engine are manifold; most important of merit being, its relative lightness corresponding to the ratio of port area provided, the simplicity of its structure, the ease by 'which it can be successfullylubri- Vcated yfrom the oilr vapors presentI in the crank case of the engine when inv operation, the design of cylinder block it permits tending to make conipactness possible, the minimum weight it develops in movement acceleration facilitating high engine lrotation acceleration and the substantial ratio of skirt area corresponding tothe head area which contacts the heat volume eliminates' the prob lem of heat convection from'the valve meinber in a two stroke cycle internal combustion engine, wherein a high Yfrequency of heat lperiods are developed by high speed ytwo stroke cycle operation. e Fig. 1 is vertical section taken transversely7 of the engine, the cutting line being stepped and intersecting the axes of the working cylinder andthe one of the auxiliary piston cylinders whichis adapted to the admission valve function. l y c Fig. 2 is a cross sectional view of the "engin'e'on the line 2-2 of Fig. 1. y

Fig. 3 isa vertical longitudinal section taken on line 3 3 of Fig. 2, the cutting line intersecting the axes of the pair of auxiliary pistons andrespective cylinders. Fig. fis avcrtical sectiontransversely of the engine taken on line 4-4 of Fig. 2, indicating the crank relationship of the working piston crank and the one of the two auxiliary pistoncranks which auxiliary piston is adapted to admission valve function. i

Figa 5 is a vertical section transversely of the engine taken on line .55 of Fig. 2, indicating the relationship of the working piston crank and the one of the two auxiliary piston cranks whichI auxiliary piston is adapted to providecounterinflueiu'cs to the other of the pair of auxiliary pistons.

Fig. 6 is adiagrannnatic view illustrating the diametrically opposedV position of the two crank pins to which the pair of related counterbalancing auxiliary pistons are con-- nected. l y

Referring by numerals to the accempanying drawings, 10 designates a cylinder block, to which a cylinder head 11 is attached, supporting the cylinderblock is a crank case 12, a'working cylinder 13 -is formed inthe cylinder block, a pairof axially parallel auxiliary piston cylinders 14- and 15l are formed in the `cylinder block. 1

f. An auxiliary piston 16 is arranged for reciprocatory movement within the cylinder 14ga secondl auxiliary piston 17 is arranged for reciprocatory movement within the cylinl23 and 24 are formed of the auxiliary crank shaft, the crank pin 23 being disposed substantially diametrically opposite the crank pin 24. y l.

Connecting rods 25 and 26 are employed in the usual manner connecting the auxiliary pistons to the auxiliary shaft A one to one timing drive is indicated by numerals 27 and 28 von Fig. 1,- illustrating lthe rotationrelativity between vthe crank shaft 19' and theA auxiliary'y crank shaftv 22. It is to be Vunderstood that the pair of auxil iary' pistons to a given combustionchamber may be actuatedby direct connection with the ,main crankshaft if desired without departing from'the spiritof the invention. l A combustion chamber compression clearance .29 is formed in the cylinder lhead and joins the cylindrical chambers of the work-v ing-cylinder and thetwo auxiliaryl piston cylinders into one common chamber. l y

l A series of fresh charge admission portsA 3() are formed in the wally of one cylinder only ofthe pairr of auxiliary piston cylinders, a fresh charge passage connnunicating duct 3l extends aroundv the saidA auxiliary piston cylinder having the admission ports, the 4said admission por-ts are formed inA an annular row the plane of which row is Aat right angle to the axis of the respective cylinderand thc fresh charge passage communicating duct 31 heilig y formed in4 communication with each of the admissionportsof the annular row. An ignition device-32 is screwed into a threadedaperture 33, preferably located in the cylinder headand in aliosition which will facilitatethe sparking tcru'iinals protruding' the'l wall of the combustion chamber directly headward of the one of the auxiliary piston cylinders in which is formed ythe fresh charge admission ports.

An exhaust portlv is formed of the working cylinder 13. Y ,y

kA fresh charge induction blower 35 is karranged in passage'communication vwith` the fresh charge kcommunieating passageV 81 of the cylinder blockby a discharge pipe 36.

A fuel` mixing device 87 is suspended from the blower. Any suitable'blower may he iny the wall 80 journaled inthe crank case, two crank pins used which will supply an induction force tor the admission ot' fresh charge into the combustion chamber.

v'litfivill bel seen by Fig. l, that the Working piston is in a position after crank end dead center with ythe working crank rpin Q0 substantially 400 aiter crank end dead center,

the' corresponding location ot' the auxiliaryl crank pin' 23 toivliich the one of the auxiliary pistons ot the auxiliary cylinder crank pin to which the auxiliary piston oty the cylinder having the admission ports is connected.

The operation of'niy improved internal combustion engineis as follows: Assuming the reciprocatory and rotary pprts to be in the position as illustrated. in the accompanying drawings, the Working piston moving headivardly aivay from crank end dead center, at this moment the head oi' the said piston crosses the plane ot' the head- Ward edge of the exhaust ports, cutting off exitpassage communication between the exhaust ports and the combustion chamber.

The auxiliary aiston adapted to the auxiliary cylinder ot which cylinder is formed the admission ports is in the position ot crank end dead center, the admission portsI being lully open to the combustion chamber. t this moment the second auxiliary piston is in a position of head end dead center.

As the Working piston moves headwardly, the admission port auxiliary piston also mores lwadivardly to a position with rela-- tire crank pin substantially 400 after crank end dead center ativhich moment the crank pin to which the second auxiliary piston of the auxiliary cylinder having no ports is connected is in the position substantially zitter head end dead center, balancing the iii-st auxiliary piston, and the crank of tho main shatit to `which the Working piston is connected will be in a rotative position substantially after crank Lend dead center.

Ait this moment the head edge of the auxiliary piston of the auxiliary cylinder having' the admission ports will pass headwardly beyond the plane of the headward edge ot the admission ports, cutting oil inlet passage communication With the combustion chamber. Further movement orfthen'forking' piston andthe one of the auxiliary pistons" developing" compression" of ,the fresh ilo counterathe driif'ing eifect,anti-rota-` chargc in the compression clearance of the; lt will be `understood combiistion chamber. that the stroke sweep of the Workingplston only is productive of compression since the tiro auxiliary pistons,y one of which is adapted to the admission yvalve function, are continuously moving in opposite direction their respective stroke sweep displacen'ient being;` balanced thereby. l

Upon the arrival ot the Working piston at head end dead center, compression being' complete, ignition will take place, combustion 'tollowmg the expansion following-combustion driving` the working piston crank- 'ardly through the expansion cylinder. At'` the .uioment the Working piston is at headA end deadv center and the time initial combustion is laused to occur the crank pin t0 which the auxiliary piston adapted to admission port valve function Will be iny a relative position substantially'V 40 before head end deadcen'ter, the relative positionv oit the. other crank pin to which the other of the tivo auxiliary pistons is connected being" substantially' 400 before crank end dead'center.

'liius it will be understood that thepressure rise in the combustion chamber resulting it'rom combustion of the compressed fresh gaseous mixture will be :ineffective in the development ot anyrnet' power transmission to the rotary element to iv'hich it is mechanically associated in either direction, clock or anticlockwise relative to rotation, the auxiliary piston crank pins being oppositely disposed, balance both, the reciprocatory inertiav forces and the piston areas, which piston areas contact the internal pressure.

lilith 'lurl'hcr crankivard movement oit the ivorking` piston, the head edge ot the said piston will pass crankwardly beyondy the plane of the head edge of' the exhaust ports, establishing' thereby wexit passage communication.between. the cxhaustpassage and the combustion chain'ber and providing' an outletior the release ot the spent products of combustion expanded in power development Within the combustion chamber.

Since the exhaust and admission ports respectively are of a height axially With respect to the respective cylinders oi which the said ports are formed ol' stroke movement respective to each piston corresponding to 400 of crank rotative movement to or from crank end dead center itv is evuident that the admission ports will not be opened to the combustion chamber until the exhaust ports have been open for a duration" of time4 correspondingjto 40@ ot crank rotative movement. also the admission ports will'notloe'4 closed until the ezdiaustl ports have' been closed for a period ottime'corresponding to 10Q of crank'rotative movement; e

It is to be' understood that the" timing reflation between the respective crank pins as' .fili

lili! described is presented to provide a specilic example of the working combination ot parts and clearly describe the function.

The relative crank positions may be changed as may be desired to provide a ditferent timing between the exhaust period and the admission period, or minor changes in the size,'form and construction of the various parts may be made and substituted for those herein shown without departing from the spirit of my invention, the scope of which is set forth in the appended claims.

I claim as my invention:

1. In an internal combustion engine, a`

compression clearance chamber, a combustion cylinder and a pair of pi-ston valve cylin-ders, the chambers ot the three cylinders being formed in `common with the compression clearance chamber, pistons arranged for reciprocatory movement within the three cylinders, three cranks of the engine, the piston ot one of the three cylinders being connected to each of the three cranks, exhaust ports formed in the intermediate portion ofthe combustion cylinder where it lis uncovered when the piston within' said combustion cylinder is at the crankward end ot its stroke, charge admission ports formed in a second cylinder of the three cylinders, the crank to which the piston ot the cylinder yhaving the exhaust ports is connected being' rotatively disposed in advance of the crank to'which the piston of they cylinder having the charge admission ports is connected, the crank to which the piston'ot the third cylinder is connected being disposed rotatively diametrically opposite the crank to which the piston of the cylinder having the admission ports is connected, the dimensions oli the said' two oppositely disposed cranks and the relative parts attached thereto being respectively alike.

2. In an internal combustion engine, ra

combustion cylinder and a pair of piston( valve cylinders, the chambers ot the three cylinders being -joined into a 'common chamber, one piston arranged for reciprocatory movement within each of the three vcommonly joined cylinders, vports formed in the combustion cylinder and one ot' the piston valve cylinders, the ports in the combustion cylinder being adapted to exhaust, the ports of l the other oi the two ported cylinders being adapted to fresh charge admission the exhaustport in the combustion cylinder being located ata poi-nt where Ait is uncovered 'when/the piston in said. cylinder is at the crankward end ot its stroke, the stroke sweep ot thevpiston of thc cylinder having the exhaust ports providing gaseous compression and expansion alternately successively by the stroke movement of the respective piston of the saidl cylinder to the volume 'of the commoncombustion chamber, the stroke movement of the pistons within the remain- Lerares ing two cylinders of the given three cylinder combustion unit providing gaseous compression and'expansion synchronously to the volume of the said common combustion chamber. j

3. In anr internal combustion engine, a three cylinder combustionA unit, a threeV cylinder combustion chamber, a Vpiston arranged :for reciprocatory vmovement within each of the three cylinders, means'ot imparting reciprocatory movement of continuous two stroke cycle time of fixed relation to the ypiston-s of the said three cylinders, the stroke movement oli'I one ott the said three pistons providing alternately and uniformly a. displacement variation to the three cylinder combustion chamber the wall of the cylinder Within which operates the piston that provides alternate and uniform displacement variationbeing provided intermediate its ends with an exhaust port that is uncovered when the piston within said cylinder is at the crankward end of its stroke, the stroke movement ot' the two pistons within the remaining two of the three cylinders of a giyen combustion chamber being synchronously opposite.

fl. In an internaly combustion engine, a compression clearance chamber, three cylinders, the chamberswithin the said three cyl* inders beingicommonly joined by the said compression clearance chamber, one piston arranged for reciprocatory movement within each of the said three cylinders, 'means of associating the three pistons in iixed stroke time relation, one of the three pistons being oi large stroke sweep displacement, the remaining two pistons being ot small stroke sweep displacement, the stroke sweep` displacement of the said two pistons having small stroke sweep displacement being equal, exhaust ports formed inthe cylinder the piston of which is of large stroke sweep displacement which exhaust ports are arranged so that they are uncovered only when the piston within said cylinder is at the crankward end of its stroke, admission ports formed in one, of the remaining two cylinders of -the said three cylinders commonly joined by the said compression clearance chamber, the stroke movement ot the piston ot large stroke sweep displacement being of the cylinder having the exhaust ports being in advance with respect to the stroke movement oit the piston within the one ot the remaining ytwo cylinders having the admission ports and the stroke movement ot the two pistons having small stroke' sweep displace-- ment being synchronously opposite in direction. i

5. In an internal combustion engine, a compression andy expansion cylinder, a piston arranged for reciprocatory movement within the said cylinder, exhaust ports formed in the saidcylinder at a point where they vrare uncovered only while lthetpiston Within said cylinder isat thecrankward end ot' its stroke, t-woauxiliary cylinders, the chambers ot' the ,compression and expansion cylinder and the chambers of the said two Vauxiliary cylinders being joined by a common clearance chamber, inlet ports toi-med in one yof the said two auxiliary cylinders, a piston arranged `for reciprocatory movement within each of the said two auxiliary cylinders, the stroke movement of the piston within the cylinder having the exhaust ports 4being adapted to ett'ect the common displacesynchronous in opposite direction, means of maintaining a fixed timed stroke relation between the three pistons oi' the said three cylinders Jforming a given common chamber, and ignition means located in the common clearance chamber directly headward of the cylinder having the inlet ports.

G. In an internal combustion engine, a two stroke cycle combustion unit ot' three cylinders, a piston arranged for reciprocatory movement in each of the three cylinders, exhaust ports formed in one of the three cylinders at a point where they are uncovered only while the piston within said cylinder is at the crankward end of its stroke, inlet ports formed in a second cylinder of the three cylinders, a gaseous clearance chamber formed of the engine, the said gaseous clearance providing a common clearance chamber for the piston stroke sweep displacement of each of the three cylinders, the reciprocatory movementof the piston within the cylinder having the exhaust ports providing compression and expansion to the gaseous charge. of the engine and valvular function to the said exhaust ports, the reciprocatory movement of the piston within the cylinder having the inlet ports providing inlet port registration with the said gaseous clearance chamber of the engine, the reciprocatory movement of the piston within the third cylinder providing synchronously a counterbalance of reciprocatory weight inertia and stroke sweep displacement exactly equal in value the reciprocatory weight inert-ia and displacement of the respective stroke sweep of the piston ot the cylinder having the inlet ports.

7. In a two stroke cycle internal combustion engine, a power cylinder, a clearance chamber to the chamber of the said cylinder, a piston arranged for reciprocatory movement within the said cylinder, exhaust port-s formed vin the wall ,of the said. cylinderata point where they are ,uncovered only while vthe `piston within said ycylinder .is at the crankward end of its stroke, a pair ofI cylinders formed to the sideof the said power cylinder, a lateral extension ot' the said clearance chamber, the said, lateralextension kcommunicating withveach of the chambers of the said pair of cylinders, .inlet .ports formed in the Wall of one of the said pair .of cylinders, pistons arranged forreciprocatory movement within :each offthevsaid l, pair ofcylinders, the piston withinthe one ofthesaid pair `oit cylinders having .the inlet ports providing a valve means to the said inlet ports, the piston within the other of the said pair or' cylinders providing a counterstroke sweep displacement of equal volume to the stroke sweep displacement of the pist0n of the one of the said pair of cylinders having the inlet ports, three cranks of the engine to which the pistons of the said three cylinders are separatel means oi maintaining the stro re movement of the three pistons in fixed stroke time relaconnected,

tion and the arrangement whereby the crank.

to which the piston within the cylinder having the exhaust ports is connected is relatively rotatively disposed in advance of the crank to which the piston within the cylinder having the inlet ports is connected providing exhaust port opening and closing lead to the time of inlet port opening and closing.

8. In an internal combustion engine, three cylinders, a common compression clearance chamber joining the said three cylinders, one of said three cylinders being provided with inlet ports, another ,of said cylinders being provided with exhaust ports arranged so that they are uncoveredonly when the piston within said cylinder is at the crankward end of its stroke, pistons arranged for reciprocatory movement within each oi the three cylinders, three cranks of the engine, each of the three pistons being separately connected to one of the three cranks, one of the cranks being arranged relatively rotatively in advance of the second crank,` the third crank being arranged relatively rotatively diametrically opposite the said second crank and the stroke sweep displacement ot the two pistons connected to the said second and third cranks which cranks are disposed diametrically opposite being of identical volume. v

9. The combination in a two stroke cycle internal combustion engine, of a Working cylinder, exhaust ports formed in the working cylinder, and located sohthat they are uncovered only when the piston within said working cylinder is at the crankward end of its stroke, a piston arranged for reciprocatory movement within the working cylinder, two auxiliary cylinders, inlet ports formed in one of the said two auxiliary cylinders, a gaseous clearance chamber common 'to the Chambers, the 'working cylinder and the two auxiliary cylinders," of the reciprocatory stroke sweep displacement of the two piftons of theV twov auxiliary cylinders 'being equal,` the stroke sweep displacement of the pistons of the auxiliarycylinders beingless Y volume than the'strole sweep displacement `of the 'piston of the working cylinder, of thel reciprocatory movement of the two pistons of the two auxiliary cylinders being synchronou'sly opposite in direction, the reciproycatory movement of the piston of the workingl cylinder being in stroke position relatively in advance of 'the stroke position of the piston of the two auxiliary cylinders in whichl cylinder the inlet ports are formed, means providing a timed stroke relation of reciprocatory movement between the Vworking piston and the two pistons of the two auxiliary cylinders and ignition means located in the wall of the clearance chamber ldirectly adjacent the cylinder in which the inlet ports are formed.V

In testimony whereof I aix my signature.

EVERETT R'.,BURTNETT. 

